Collision broadening and shift of the S and D rydberg levels of rubidium by He and Ar

Abstract

The effects caused by collisional interactions of He and Ar on the high lying states of Rb are presented. Using both direct and hybrid two-photon excitation we report the broadening and shift of the Rb 5 2S→ n 2S(10⩽ n⩽21) and 5 2S → n 2D (8⩽ n⩽35) transitions. The perturber gas concentrations ranged from 0.40 relative density (r.d.) to 2.64 r.d. and the rate of broadening and shift has been calculated for the above transitions. When compared with previous results at much lower perturber concentrations our broadening and shift rates are similar for all n 2S and 19 2D levels except for the shift rate of the 19 2D level. The broadening and shift of the hybrid series are found to be relatively unaffected by the participation of a real intermediate state.